netfilter: limit the length of the helper name

This is necessary in order to have an upper bound for Netlink message calculation, which is not a problem at all, as there are no helpers with a longer name. Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
mariux64 · Mar 25, 2009 · af9d32a · af9d32a
1 parent e487eb9
commit af9d32a
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diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h
@@ -14,6 +14,8 @@
 
 struct module;
 
+#define NF_CT_HELPER_NAME_LEN	16
+
 struct nf_conntrack_helper
 {
 	struct hlist_node hnode;	/* Internal use. */

diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
@@ -142,6 +142,7 @@ int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 
 	BUG_ON(me->expect_policy == NULL);
 	BUG_ON(me->expect_class_max >= NF_CT_MAX_EXPECT_CLASSES);
+	BUG_ON(strlen(me->name) > NF_CT_HELPER_NAME_LEN - 1);
 
 	mutex_lock(&nf_ct_helper_mutex);
 	hlist_add_head_rcu(&me->hnode, &nf_ct_helper_hash[h]);